Struggling at low revs

[Pobski]

Hi, new to the forum and need help. My L3 has recently started to really struggle at low revs, especially when pulling away in first. The engine really bogs down, and feels as though its gonna cut out. It eventually gets going, but if the revs drop down too low in any gear, it does it again. I don't know if this is related, but it has started idling funny too. It has started going down to about 1,000rpm, instead of 1,500rpm. Another problem, maybe related, is that when I ride with the lights on full, it drains the battery. So much so, that the bike just cut out on Sunday, and I had to bump start it.

I'm not mechanically minded, so any help would be really appreciated.

[extonyg]

i would start with checking that the battery is charging when the engine is running......should be about 14v at idle and raise up with the revs i would get the battery problem sorted first then start looking at the running issue.
hope this helps

[RedexRobB]

I agree with that, a knackered battery could be causing all those problems i reckon. As above reply, 14-14.5 volts at about 4K revs is the figure your looking for. If its any higher than that or lower than 13v then your probably looking at changing the regulator/rectifier. If its what it should be then your battery might be having problems holding its charge in which case youll need a new one.

[Pobski]

Thanks for the advice. Okay, at idle (just over 1,000rpm), it reads around 14.60volts. With the engine revving to 4,000, it reads around 16.90volts. Does this mean its the regulator/rectifier then?

Thanks again for the advice!

[zimm]

shouldnt exceed ~15v, so yeh, looks like reg/rec

[Pobski]

Guess I'll start having a shop around then. Cheers y'all

[Pobski]

Right, I have replaced the reg/rec, and it hasn't helped the bike at low revs. The reading from the battery is still too high. My Dad has suggested it may be the generator, but I have no idea what it could be. Any ideas?

[RedexRobB]

have you changed the battery?

Could be the generator, test is in the naual here:

http://www.zxrworld.co.uk/zxr400/manual.html